Lose about 400 lbs before getting on the treadmill again Harish.
Kidding.
Seriously, probably a fuse or a power supply issue.  I'd check out the Treadmill Report, it's pretty thorough and straightforward.  Just search "Treadmill Report," it's really good to have for anybody that owns a treadmill.  
Also check out these vids:
http://www.fit-senior.com/acatalog/Online_Catalog_Treadmill_Repair___For_Service_Technicians_41.html
They gave me some insight on some diagnostics that you can perform to find out the problem.
                
 Yosh
                
 January 2008